Today at 1358hrs, Rescue Engine 40 along with Engine Co. 25 (Clinton), Truck 32 (Allentown Road), Rescue Squad 27 (Morningside) and Battalion Chief 7 were alerted to respond to the 11500blk of Cosca Park Pl for the reported investigation of an appliance. Rescue Engine 40 responded with four personnel. Engine Co. 25 arrived on the scene to find a working fire with heavy smoke evident. Battalion Chief 7 arrived on the scene, established command, requested the remainder of the box and the working fire dispatch to be sounded. The remainder of the box included Engine 472 (Allentown Road), Paramedic Engine 42 (Oxon Hill) and Tower 21 (Oxon Hill), the WFD brought Ambulance 329 (Allentown Road), Medic 25 (Clinton), EMS Duty Officer, Northern Safety Officer, Battalion Chief 5. After further evaluation, the units found a room well off on the second floor. The crew from the Rescue Engine completed both the primary and secondary searches in the fire building. Command soon held 25, 40, 32 and 27.